If you’re working with a large site that gets a lot of traffic or are using advanced segments, you could be running reports with a lot of sampling. Sampling is where Google basically takes a scoop of data from the whole gallon of ice cream and makes conclusions about the rest based on that scoop. (I really shouldn’t blog when I’m jonesing for a chocolate shake!)
Anyway, Google gives users an indicator that their data is being sampled, but it’s so small and subtle many miss it. So you have to train your eye to look for this symbol in the upper-right corner of your reports, right under the date range:
Google kind of slipped this little bugger into the UI quietly this past year under the guise of providing your data faster. However, moving it to the right will cut the degree of sampling applied to your data in half. So if you see it, always, always, always click it and move the slider all the way to the right like so to take some of your data back:
In the report I’m using as my example, because the report was based on 52% of visits, when I moved the slider all the way to the right, it removed sampling altogether (because doubling that takes us to 100%). And that made me feel like Robin Hood to my client. (Granted, I have a seriously over-active imagination!) In most cases you won’t remove all sampling, but you can at least double the amount of data Google uses in its sample population.
Hi again Annie, was looking through your analytics audit in which you have an entry “Does the site have excessive sampling? If so, is it b/c they have more than one website in a property?”. I’m confused what the last bit means. Is it just having the same UA code on more on than site? Thanks for your help as always 🙂
No, it’s fine to have more than one GATC on a site (as long as it doesn’t cause too much lag). If you look in your Admin section you’ll see Account to the far left, then Property, then View (FKA Profile). There should only be one site under Property. Some people put multiple sites under one property, which can cause sampling issues if they’re large websites. Better to group them under one account, rather than in the same property.
Thanks! Yeah i wasn’t talking about more than one code on one site but rather one code on more than one site (as done in roll up reporting). Anyways doesn’t matter the real problem is …
I think I’m confused because I thought websites *were* properties. Did you mean a scenario where someone puts the same tracking code on two websites and tries to separate them out in the views?
Thanks for your patience! I realise I’m probably being very daft
Not sure how else to explain it, Peter. Maybe this post from LunaMetrics will help? http://www.lunametrics.com/blog/2013/06/24/solutions-google-analytics-sampling-problems-8-ways-data/
Okay thanks read it closely and understand now.
sorry typing too fast last bit should read “same UA code on more than one site?”